Replace Ghosting Image for rankingImages

[GGsource]

Replace the semitransparent image that shows when dragging something with a custom version. This is half-implemented but currently just shows a square with the number of items selected.

• Make a properly centered drag-representation that groups the previews of all selected images.

Maybe as a stack? or square with 4 little images inside? If there's more than 4 selected it just shows the first 3 and then a +x on the 4th spot with however many more there are?

Alternatively maybe this ghost isn't needed at all?